-LRB- CNN -RRB- -- Osiel Cardenas Guillen , the former head of a powerful Mexican drug cartel , was sentenced to 25 years in prison and will forfeit to the United States $ 50 million in illegal proceeds , a judge ruled .

Cardenas Guillen , 42 , was the leader of the Matamoros , Mexico-based Gulf cartel until his capture in 2003 . He was subsequently extradited to the United States to face drug trafficking charges in 2007 .

U.S. District Judge Hilda Tagle handed down the sentence Wednesday , following an earlier guilty plea by the drug kingpin .

Under Cardenas Guillen 's leadership , the Gulf cartel was responsible for smuggling thousands of kilograms of cocaine and marijuana into the United States , the FBI said in a news release .

Read the original indictment

According to the FBI , in 1999 Cardenas Guillen threatened to kill a U.S. undercover sheriff 's deputy . In another incident , he threatened the lives of two U.S. agents .

`` The successful prosecution of Cardenas Guillen underscores the joint resolve of the United States and Mexico to pursue and prosecute the leadership of the drug trafficking cartels , dismantle their organizations and end the violence and corruption they have spawned , '' U.S. Attorney Jose Angel Moreno said .

Cardenas Guillen pleaded guilty to five felony charges , including conspiracy to possess with intent to distribute , conspiracy to launder money and threatening to assault and kill federal agents .

Tagle also fined Cardenas Guillen $ 100,000 and ordered him to five years probation once his sentence is served . He is not eligible for parole .

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Sentence handed down Wednesday after drug kingpin 's earlier guilty plea

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FBI : Cardenas Guillen in 1999 threatened to kill an undercover sheriff 's deputy

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He also threatened the lives of two U.S. agents